/*
 * Copyright (c) 2017-2019 Tencent Group. All rights reserved.
 * License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

#include <string.h>
#include <stdio.h>

#include "qcloud_iot_import.h"
#include "utils_getopt.h"

static int  utils_opterr = 1;           /* if error message should be printed */
static int  utils_optind = 1;           /* index into parent argv vector */
static int  utils_optopt;               /* character checked for validity */
static int  utils_optreset = 1;        /* reset getopt */

char*       utils_optarg; /* argument associated with option */

int utils_getopt(int nargc, char* const* nargv, const char* options)
{

#define BADCH   (int)'?'
#define BADARG  (int)':'
#define EMSG    ""

    static char* place = EMSG;  /* option letter processing */
    const char* oli;            /* option letter list index */

    if (utils_optreset  || !*place) { /* update scanning pointer */
        utils_optreset = 0;

        if (utils_optind >= nargc || *(place = nargv[utils_optind]) != '-') {
            utils_optind = 1;
            utils_optreset = 1;
            place = EMSG;
            return (-1);
        }

        place++;
    }

    /* option letter okay? */
    if ((utils_optopt = (int) * place++) == (int)':' ||
        !(oli = strchr(options, utils_optopt))) {
        /*
        * if the user didn't specify '-' as an option,
        * assume it means -1.
        */
        if (utils_optopt == (int)'-')
            return (-1);

        if (!*place)
            ++utils_optind;

        if (utils_opterr && *options != ':')
            HAL_Printf("illegal option - %c\n", utils_optopt);

        return (BADCH);
    }

    if (*++oli != ':') {                    /* don't need argument */
        utils_optarg = NULL;
        if (!*place)
            ++utils_optind;
    } else {
        /* need an argument */
        if (*place)                     /* no white space */
            utils_optarg = place;
        else if (nargc <= ++utils_optind) {   /* no arg */
            place = EMSG;
            if (*options == ':')
                return (BADARG);
            if (utils_opterr)
                HAL_Printf("option requires an argument - %c\n", utils_optopt);
            return (BADCH);
        } else                          /* white space */
            utils_optarg = nargv[utils_optind];

        place = EMSG;
        ++utils_optind;
    }

    /* dump back option letter */
    return (utils_optopt);
}
